You can also Delete the folder inside a directory or drag a directory and a list (that has the items) from within Finder, into Preview “There's no way to delete an individual file from a Preview window in iOS 8.4-11. The new Finder doesn't allow you to delete a file from a preview window when that file is open in another window in Apple's new user interface. Preview is only in windows, and you're trying to open something that is not a file, I'm not sure what the issue is here. The only thing I can think of is something about the way the folder is stored in Apple's new user interface in the user interface and the way it's stored on the file system (I don't understand how something stored in Finder can't be opened in Preview). In my opinion, this is why it's so easy to open the folder and drag to a different window from Preview: it's already in the new app folder (the only difference is not a file is in Finder, but it's in there somewhere). If I'm right, we would still be able to open the folder and drag to different windows. If this is the case, this makes a lot of sense. If it's not in the user interface, then the file doesn't exist, or it contains something we don't want to show, so we drag it from a folder to a window, or we open the app, drag it to another window (something to that effect), let the app open the file, close it, but if it's not an app-specific file in that folder, it's not going to be an issue. If that changes with iOS 11 we can be sure it will be an issue. This is my guess on the new user interface and the way files are accessed in iOS. In my experience, the changes have more to do with how app files are installed to the system and are also used by the system to access app folder and open app specific folders in the Finder. I'm sorry that I don't get a chance to verify this or anything else about the new interface, but that's my thought on the new interface.” Mac world, December 26, 2016, How do I delete files open in Preview? — Web Design Forums This article is from 2014. If you want to delete “A PDF document opens in Preview” and “A PDF document opens in Preview, and then it closed”. Use a text editor.